Microcapsule dispersions

Abstract

This invention concerns with an improved microcapsule dispersion prepared by adding the following components to a known microcapsule dispersion containing PVA; a pulp having a specific weighted average fiber length, another type of pulp, carboxymethyl cellulose and/or a specified periodic acid type compound, and is characterized by overcoming the drawbacks of known microcapsule dispersions attended by use of PVA.

We claim: 
     
       1. In an aqueous microcapsule dispersion used for preparing pressure sensitive manifold papers, said dispersion containing auxiliary materials of a polyvinyl alcohol and pulp, the improvement comprising said pulp being present in an amount of about 5 to about 45 parts by weight per 100 parts by weight of the capsules and being a finely divided pulp up to 80μ in weighted average fiber length, so as to substantially inhibit an increase in viscosity of said dispersion. 
     
     
       2. An aqueous microcapsule dispersion as defined by claim 1, wherein the dispersion further contains at least one compound selected from the group consisting of periodic acid or a salt thereof, each in an amount of 0.001 to 0.05 mole/l, and carboxymethyl cellulose in an amount of 0.1 to 10 g/l. 
     
     
       3. In an aqueous microcapsule dispersion used for preparing pressure sensitive manifold papers, said dispersion containing auxiliary materials of a polyvinyl alcohol and pulp, the improvement comprising said pulp being present in an amount of about 5 to about 45 parts by weight per 100 parts by weight of the capsules and being a finely divided pulp not less than 20μ in weighted average fiber length, and said dispersion further containing at least one compound selected from the group consisting of periodic acid or a salt thereof, each in an amount of 0.001 to 0.05 mole/l, and carboxymethyl cellulose in an amount of 0.1 to 10 g/l, so as to substantially inhibit the increase in viscosity of said dispersion. 
     
     
       4. An aqueous microcapsule dispersion as defined by claim 3, wherein the dispersion contains periodic acid or a salt thereof and carboxymethyl cellulose. 
     
     
       5. An aqueous microcapsule dispersion as defined by claim 3, wherein the dispersion contains periodic acid or a salt thereof.